i try to back up a dvd which content 4.5 gb movie. but when i try to copy, it pop out a mesage that show the dvd-r doens't have enough space to back up , and it will take my own risk. Also when i use mouse right click the properties of the dvd, it show that original dvd has 4.5 gb, but when i try to burn it ,it tell me that this dvd is about 4.75 gb big. so which size is correct?
The movie is probably 4500Mb which is not the same as 4.5Gb - it is as it says nearer to 4.75 Gb. A blank DVD disc described as 4.7Gb capacity can be misleading because it is infact 4380Mb(or 4.38Gb if you prefer). When it comes to blank discs just remember 4.38 and not 4.7!
I thought it was 4.38GB as well, but i have been reading that it is closer to 4.43GB. Anyway, the principle is the same.
Yes you may be right at 4.43Gb but Nero will not burn a disc a fraction more than 4.38Gb (I've tried it).
It is because in one kilobyte there are 1028 bytes. KILO = 1028 not 1000. The higher the numbers, the more the difference. Do the math. It kind of sucks i know!!!
Actually it's 1024, not 1028. (Must be a number divisable by 8) A DVD-R holds 4 700 000 000 bytes. (Or actually 4 680 000 000, but you get the idea.) 4 680 000 000/1024 /1024 /1024 = 4.38 GB
